--- /dev/null
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright 2022, Naveen Albert <asterisk@phreaknet.org>
+ *
+ * Naveen Albert <asterisk@phreaknet.org>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief If Branch Implementation
+ *
+ * \author Naveen Albert <asterisk@phreaknet.org>
+ *
+ * \ingroup applications
+ */
+
+/*** MODULEINFO
+ <support_level>extended</support_level>
+ ***/
+
+#include "asterisk.h"
+
+#include "asterisk/pbx.h"
+#include "asterisk/module.h"
+#include "asterisk/channel.h"
+
+/*** DOCUMENTATION
+ <application name="If" language="en_US">
+ <synopsis>
+ Start an if branch.
+ </synopsis>
+ <syntax>
+ <parameter name="expr" required="true" />
+ </syntax>
+ <description>
+ <para>Start an If branch. Execution will continue inside the branch
+ if expr is true.</para>
+ <note><para>This application (and related applications) set variables
+ internally during execution.</para></note>
+ </description>
+ <see-also>
+ <ref type="application">ElseIf</ref>
+ <ref type="application">Else</ref>
+ <ref type="application">EndIf</ref>
+ <ref type="application">ExitIf</ref>
+ </see-also>
+ </application>
+ <application name="ElseIf" language="en_US">
+ <synopsis>
+ Start an else if branch.
+ </synopsis>
+ <syntax>
+ <parameter name="expr" required="true" />
+ </syntax>
+ <description>
+ <para>Start an optional ElseIf branch. Execution will continue inside the branch
+ if expr is true and if previous If and ElseIf branches evaluated to false.</para>
+ <para>Please note that execution inside a true If branch will fallthrough into
+ ElseIf unless the If segment is terminated with an ExitIf call. This is only
+ necessary with ElseIf but not with Else.</para>
+ </description>
+ <see-also>
+ <ref type="application">If</ref>
+ <ref type="application">Else</ref>
+ <ref type="application">EndIf</ref>
+ <ref type="application">ExitIf</ref>
+ </see-also>
+ </application>
+ <application name="Else" language="en_US">
+ <synopsis>
+ Define an optional else branch.
+ </synopsis>
+ <syntax>
+ <parameter name="expr" required="true" />
+ </syntax>
+ <description>
+ <para>Start an Else branch. Execution will jump here if all previous
+ If and ElseIf branches evaluated to false.</para>
+ </description>
+ <see-also>
+ <ref type="application">If</ref>
+ <ref type="application">ElseIf</ref>
+ <ref type="application">EndIf</ref>
+ <ref type="application">ExitIf</ref>
+ </see-also>
+ </application>
+ <application name="EndIf" language="en_US">
+ <synopsis>
+ End an if branch.
+ </synopsis>
+ <syntax />
+ <description>
+ <para>Ends the branch begun by the preceding <literal>If()</literal> application.</para>
+ </description>
+ <see-also>
+ <ref type="application">If</ref>
+ <ref type="application">ElseIf</ref>
+ <ref type="application">Else</ref>
+ <ref type="application">ExitIf</ref>
+ </see-also>
+ </application>
+ <application name="ExitIf" language="en_US">
+ <synopsis>
+ End an If branch.
+ </synopsis>
+ <syntax />
+ <description>
+ <para>Exits an <literal>If()</literal> branch, whether or not it has completed.</para>
+ </description>
+ <see-also>
+ <ref type="application">If</ref>
+ <ref type="application">ElseIf</ref>
+ <ref type="application">Else</ref>
+ <ref type="application">EndIf</ref>
+ </see-also>
+ </application>
+ ***/
+
+static char *if_app = "If";
+static char *elseif_app = "ElseIf";
+static char *else_app = "Else";
+static char *stop_app = "EndIf";
+static char *exit_app = "ExitIf";
+
+#define VAR_SIZE 64
+
+static const char *get_index(struct ast_channel *chan, const char *prefix, int idx)
+{
+ char varname[VAR_SIZE];
+
+ snprintf(varname, VAR_SIZE, "%s_%d", prefix, idx);
+ return pbx_builtin_getvar_helper(chan, varname);
+}
+
+static struct ast_exten *find_matching_priority(struct ast_context *c, const char *exten, int priority, const char *callerid)
+{
+ struct ast_exten *e;
+ struct ast_context *c2;
+ int idx;
+
+ for (e = ast_walk_context_extensions(c, NULL); e; e = ast_walk_context_extensions(c, e)) {
+ if (ast_extension_match(ast_get_extension_name(e), exten)) {
+ int needmatch = ast_get_extension_matchcid(e);
+ if ((needmatch && ast_extension_match(ast_get_extension_cidmatch(e), callerid)) ||
+ (!needmatch)) {
+ /* This is the matching extension we want */
+ struct ast_exten *p;
+ for (p = ast_walk_extension_priorities(e, NULL); p; p = ast_walk_extension_priorities(e, p)) {
+ if (priority != ast_get_extension_priority(p))
+ continue;
+ return p;
+ }
+ }
+ }
+ }
+
+ /* No match; run through includes */
+ for (idx = 0; idx < ast_context_includes_count(c); idx++) {
+ const struct ast_include *i = ast_context_includes_get(c, idx);
+
+ for (c2 = ast_walk_contexts(NULL); c2; c2 = ast_walk_contexts(c2)) {
+ if (!strcmp(ast_get_context_name(c2), ast_get_include_name(i))) {
+ e = find_matching_priority(c2, exten, priority, callerid);
+ if (e)
+ return e;
+ }
+ }
+ }
+ return NULL;
+}
+
+static int find_matching_endif(struct ast_channel *chan, const char *otherapp)
+{
+ struct ast_context *c;
+ int res = -1;
+
+ if (ast_rdlock_contexts()) {
+ ast_log(LOG_ERROR, "Failed to lock contexts list\n");
+ return -1;
+ }
+
+ for (c = ast_walk_contexts(NULL); c; c = ast_walk_contexts(c)) {
+ struct ast_exten *e;
+
+ if (!ast_rdlock_context(c)) {
+ if (!strcmp(ast_get_context_name(c), ast_channel_context(chan))) {
+ /* This is the matching context we want */
+ int cur_priority = ast_channel_priority(chan) + 1, level = 1;
+
+ for (e = find_matching_priority(c, ast_channel_exten(chan), cur_priority,
+ S_COR(ast_channel_caller(chan)->id.number.valid, ast_channel_caller(chan)->id.number.str, NULL));
+ e;
+ e = find_matching_priority(c, ast_channel_exten(chan), ++cur_priority,
+ S_COR(ast_channel_caller(chan)->id.number.valid, ast_channel_caller(chan)->id.number.str, NULL))) {
+ if (!strcasecmp(ast_get_extension_app(e), "IF")) {
+ level++;
+ } else if (!strcasecmp(ast_get_extension_app(e), "ENDIF")) {
+ level--;
+ }
+
+ if (!otherapp && level == 0) {
+ res = cur_priority;
+ break;
+ } else if (otherapp && level == 1 && !strcasecmp(ast_get_extension_app(e), otherapp)) {
+ res = cur_priority;
+ break;
+ }
+ }
+ }
+ ast_unlock_context(c);
+ if (res > 0) {
+ break;
+ }
+ }
+ }
+ ast_unlock_contexts();
+ return res;
+}
+
+static int if_helper(struct ast_channel *chan, const char *data, int end)
+{
+ int res = 0;
+ const char *if_pri = NULL;
+ char *my_name = NULL;
+ const char *label = NULL;
+ char varname[VAR_SIZE], end_varname[VAR_SIZE + 4];
+ const char *prefix = "IF";
+ size_t size = 0;
+ int used_index_i = -1, x = 0;
+ char used_index[VAR_SIZE] = "0", new_index[VAR_SIZE] = "0";
+
+ if (!chan) {
+ return -1;
+ }
+
+ for (x = 0 ;; x++) {
+ if (get_index(chan, prefix, x)) {
+ used_index_i = x;
+ } else {
+ break;
+ }
+ }
+
+ snprintf(used_index, VAR_SIZE, "%d", used_index_i);
+ snprintf(new_index, VAR_SIZE, "%d", used_index_i + 1);
+
+ size = strlen(ast_channel_context(chan)) + strlen(ast_channel_exten(chan)) + 32;
+ my_name = ast_alloca(size);
+ memset(my_name, 0, size);
+ snprintf(my_name, size, "%s_%s_%d", ast_channel_context(chan), ast_channel_exten(chan), ast_channel_priority(chan));
+
+ ast_channel_lock(chan);
+ if (end > 1) {
+ label = used_index;
+ } else if (!(label = pbx_builtin_getvar_helper(chan, my_name))) {
+ label = new_index;
+ pbx_builtin_setvar_helper(chan, my_name, label);
+ }
+ snprintf(varname, sizeof(varname), "%s_%s", prefix, label);
+ if ((if_pri = pbx_builtin_getvar_helper(chan, varname)) && !end) {
+ if_pri = ast_strdupa(if_pri);
+ snprintf(end_varname,sizeof(end_varname),"END_%s",varname);
+ }
+ ast_channel_unlock(chan);
+
+ if ((end <= 1 && !pbx_checkcondition(ast_strdupa(data))) || (end > 1)) {
+ /* Condition Met (clean up helper vars) */
+ const char *goto_str;
+ int pri, endifpri;
+ pbx_builtin_setvar_helper(chan, varname, NULL);
+ pbx_builtin_setvar_helper(chan, my_name, NULL);
+ snprintf(end_varname,sizeof(end_varname),"END_%s",varname);
+ ast_channel_lock(chan);
+ endifpri = find_matching_endif(chan, NULL);
+ if ((goto_str = pbx_builtin_getvar_helper(chan, end_varname))) {
+ ast_parseable_goto(chan, goto_str);
+ pbx_builtin_setvar_helper(chan, end_varname, NULL);
+ } else if (end <= 1 && (pri = find_matching_endif(chan, "ElseIf")) > 0 && pri < endifpri) {
+ pri--; /* back up a priority, since it returned the priority after the ElseIf */
+ /* If is false, and ElseIf exists, so jump to ElseIf */
+ ast_verb(3, "Taking conditional false branch, jumping to priority %d\n", pri);
+ ast_channel_priority_set(chan, pri);
+ } else if (end <= 1 && (pri = find_matching_endif(chan, "Else")) > 0 && pri < endifpri) {
+ /* don't need to back up a priority, because we don't actually need to execute Else, just jump to the priority after. Directly executing Else will exit the conditional. */
+ /* If is false, and Else exists, so jump to Else */
+ ast_verb(3, "Taking absolute false branch, jumping to priority %d\n", pri);
+ ast_channel_priority_set(chan, pri);
+ } else {
+ pri = endifpri;
+ if (pri > 0) {
+ ast_verb(3, "Exiting conditional, jumping to priority %d\n", pri);
+ ast_channel_priority_set(chan, pri);
+ } else if (end == 4) { /* Condition added because of end > 0 instead of end == 4 */
+ ast_log(LOG_WARNING, "Couldn't find matching EndIf? (If at %s@%s priority %d)\n", ast_channel_context(chan), ast_channel_exten(chan), ast_channel_priority(chan));
+ }
+ }
+ ast_channel_unlock(chan);
+ return res;
+ }
+
+ if (end <= 1 && !if_pri) {
+ char *goto_str;
+ size = strlen(ast_channel_context(chan)) + strlen(ast_channel_exten(chan)) + 32;
+ goto_str = ast_alloca(size);
+ memset(goto_str, 0, size);
+ snprintf(goto_str, size, "%s,%s,%d", ast_channel_context(chan), ast_channel_exten(chan), ast_channel_priority(chan));
+ pbx_builtin_setvar_helper(chan, varname, goto_str);
+ } else if (end > 1 && if_pri) {
+ /* END of branch */
+ snprintf(end_varname, sizeof(end_varname), "END_%s", varname);
+ if (!pbx_builtin_getvar_helper(chan, end_varname)) {
+ char *goto_str;
+ size = strlen(ast_channel_context(chan)) + strlen(ast_channel_exten(chan)) + 32;
+ goto_str = ast_alloca(size);
+ memset(goto_str, 0, size);
+ snprintf(goto_str, size, "%s,%s,%d", ast_channel_context(chan), ast_channel_exten(chan), ast_channel_priority(chan)+1);
+ pbx_builtin_setvar_helper(chan, end_varname, goto_str);
+ }
+ ast_parseable_goto(chan, if_pri);
+ }
+
+ return res;
+}
+
+static int if_exec(struct ast_channel *chan, const char *data) {
+ return if_helper(chan, data, 0);
+}
+
+static int elseif_exec(struct ast_channel *chan, const char *data) {
+ return if_helper(chan, data, 1);
+}
+
+static int end_exec(struct ast_channel *chan, const char *data) {
+ return if_helper(chan, data, 2);
+}
+
+static int else_exec(struct ast_channel *chan, const char *data) {
+ return if_helper(chan, data, 3);
+}
+
+static int exit_exec(struct ast_channel *chan, const char *data) {
+ return if_helper(chan, data, 4);
+}
+
+static int unload_module(void)
+{
+ int res;
+
+ res = ast_unregister_application(if_app);
+ res |= ast_unregister_application(elseif_app);
+ res |= ast_unregister_application(stop_app);
+ res |= ast_unregister_application(else_app);
+ res |= ast_unregister_application(exit_app);
+
+ return res;
+}
+
+static int load_module(void)
+{
+ int res;
+
+ res = ast_register_application_xml(if_app, if_exec);
+ res |= ast_register_application_xml(elseif_app, elseif_exec);
+ res |= ast_register_application_xml(stop_app, end_exec);
+ res |= ast_register_application_xml(else_app, else_exec);
+ res |= ast_register_application_xml(exit_app, exit_exec);
+
+ return res;
+}
+
+AST_MODULE_INFO_STANDARD_EXTENDED(ASTERISK_GPL_KEY, "If Branch and Conditional Execution");
projects / thirdparty / asterisk.git / commitdiff
